Known examples of such an output device include a device described in Patent Literature 1 (Japanese Unexamined Patent Publication No. 2010-105111). The known device is structured as follows.
Two left and right wedges (a fastening driving wedge and a release driving wedge) are disposed respectively to the left and right of a lower half portion of an output rod (fastening-release driven wedge). An upper inclined surface of the left wedge is structured to be capable of fitting on an upper inclined surface of the output rod, and a lower inclined surface of the right wedge is structured to be capable of fitting on a lower inclined surface of the output rod.